Consequently, there is no simple "Save as Version 2020" button. To "downgrade" a file, we have to strip away the proprietary InDesign data and use a universal format, or use a specialized tool to trick the software.
If you could save a file with those features back to InDesign CS6, the older version would crash or ignore critical data. Instead of risking data loss, Adobe forces a one-way upgrade path. That means you need a —and the best one is the IDML format . how to convert indesign file to older version
For users who frequently work with clients on different versions and don't want to manually export every time, dedicated software can automate the process. Consequently, there is no simple "Save as Version
You can save assets (text, colors, images) to a shared CC Library, but this does not convert a whole document. For full documents, stick to IDML. Instead of risking data loss, Adobe forces a
File > Export .
To convert an Adobe InDesign (.indd) file to an older version, the most reliable method is exporting it as an InDesign Markup Language (.idml)